||T. H. Wood, C. A. Burrus, J. S. Weiner, D. S. Chemla,
D. A. B. Miller, T. C. Damen, D. L. Sivco and A. Y. Cho, "Long
Wavelength, Room Temperature Observation of Excitons and 2 Dimensional Electron-hole
States in Multiple Quantum Wells (MQWs)," Inst. Phys. Conf. Serv. No. 74; Chapter
9, Proc. Int. Symp. on GaAs and Related Compounds, Biarritz, 1984, 687-688.
the first time, room temperature exciton resonances have been observed at long wavelength.
MQWs of Ga.47 In.53 As/Al.48 In.52 As were prepared in a pin doped configuration by
molecular beam epitaxy. Absorption spectroscopy from room to Helium temperature reveals 5
features, identified as transitions between subbands and as confined exciton resonances.
We deduce the conduction and valence band discontinuities to be 0.44 and 0.29 eV,
respectively. These results suggest that quantum well devices at long wavelength should be